Carbon Dioxide → HCID 69956754, compound

Participants

Reaction Conditions

Reaction Steps

Carbon dioxide was added in small lumps to a flask against a fast flow of nitrogen. The flask was then sealed under a nitrogen bubbler and cooled to the −78° C. THF was added to cover the CO2 and the mixture stirred. The cooled lithiodithienothiophene was added dropwise via syringe and a violent reaction was observed resulting in the formation of a yellow suspension. Once addition was complete the mixture was allowed to warm to r.t. during which time the mixture turned to an off white colour. After stirring for a further 30 min. water (30 cm3) was added and the mixture turned to a light green/brown solution. This was washed with ether (2×20 cm3) and the organics discarded. The aqueous layer was acidified by the addition of HCl (10 cm3, 5 M) which precipitated out a fine yellow solid. Recrystallisation was attempted in 33% acetic acid. A fine, insoluble suspension remained after heating and this was left to further crystallise overnight to give the title compound as a fine yellow/green powder (286 mg, 61%); δH 7.31, (1H, d, J5.1), 7.56 (2H, d, J5.1), 7.94 (1H, s); v max/cm−1 (KBr) 3090 m, 2823 m, 2559 m, 1652 s, 1504 s, 1470 w, 1428 s, 1311 s, 1265 m, 1164 m, 928 s, 750 s, 716 s and 602 s; m.p. 276° C. (sublimes) m.p.(lit.reference 29) 275-277° C.)

Provenance & Evidence